Silver Lake Reclamation Project

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2013 National Association of Abandoned Mined Land Programs

Abandoned Mine Land Reclamation Award Nomination

Submitted May 6, 2013

Project Name: Silver Lake Project

Project Location: Silverton, San Juan County, Colorado

Submitted by:

Colorado Division of Reclamation, Mining and Safety

Inactive Mines Reclamation Program

1313 Sherman Street, Room 215

Denver, Colorado 80203

Kirstin Brown, Project Manager

Steve Renner, Senior Project Manager

Project Details:

Reclamation Construction Begun: June 26, 2012

Reclamation Construction Completed: September 15, 2012

Reclamation Construction Cost (OSMRE only): $265,900.00

Reclamation Construction Total Cost: $564,875.00

Parties Involved in Reclamation Process:

Project Design, Bidding, Construction Management: Colorado Division of Reclamation, Mining and Safety - Inactive Mine Reclamation Program

Project Partners:

Office of Surface Mining, Reclamation, and Enforcement

Colorado Department of Public Health and Environment

American Smelting and Refining Company Trust

Animas River Stakeholders Group

K and P Property Design, LLC

Colorado Division of Reclamation, Mining and Safety

Mountain States Historical

San Juan County Historical Society

Bureau of Land Management

Silver Lake Reclamation Project

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Introduction

The Silver Lake hardrock mine reclamation project is located in San Juan County in southwestern

Colorado, four miles east of the town of Silverton. At 12,186 feet elevation, Silver Lake is a high

mountain “hanging lake” or tarn, located at the end of a steep 1.5 mile pack trail from the trailhead at

the Mayflower Mine Road in lower Arrastra Gulch. Elevations of the project area are extreme,

ranging from 11,400 to 13,200 feet. The glacially carved topography of Silver Lake Basin is

excessively steep and rugged and the climate is harsh. Frigid temperatures are encountered most of

the year, accompanied by tremendous avalanche danger in winter and spring.

The project was developed as a joint effort between the Colorado Division of Reclamation, Mining

and Safety (CDRMS), the Colorado Department of Public Health and Environment (CDPHE), and

the Animas River Stakeholders Group (ARSG) to safeguard mine openings on properties belonging

to the American Smelting and Refining Company (ASARCo) around Silver Lake. CDPHE manages

funding for safeguarding and environmental restoration of ASARCo properties in San Juan County

as part of a court-ordered ASARCo bankruptcy settlement with Colorado. CDRMS’s Office of

Surface Mining Reclamation and Enforcement (OSMRE) funding and State Severance Tax funding

were used to safeguard the hazardous legacy mine openings, so that a significantly larger portion of

the ASARCo settlement funds can instead be utilized for large scale environmental restoration

projects to remediate acid mine waste and acid mine drainage sites in the watershed.

Silver Lake Mine Safety Closure Map, showing the location of Silverton and the ASARCo claims.

Silver Lake Reclamation Project

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Silver Lake Mining History

The Silver Lake claim was staked by John Reed and prospecting in and around Silver Lake began in

1876. At that time, the Silver Lake, Iowa, Royal Tiger, and Buckeye mines on the edges of the lake

were some of the richest mines in the State of Colorado. The Silver Lake Mine was one of the

largest and most complex mines in the American West. At one point, the Silver Lake Basin housed

500 workers year round in boarding houses, one of which was 5 stories tall, with running water and

flushing toilets at the turn of the century. Continually developed by The Stoiber family, Silver Lake

Basin can lay claim to the longest aerial mining tram, one of the first AC power grids and largest

power plants, as well as innovative milling practices for the time period. In 1901, the Guggenheim

family purchased the Silver Lake mining empire from Edward Stoiber, and in 1903 the Guggenheim

operations merged with the American Smelting and Refining Company (ASARCo). ASARCo was

keen on owning and operating mines in Silverton to feed its smelter located downstream in Durango,

Colorado. ASARCo was the primary landowner in Silver Lake Basin until its bankruptcy in 2005.

The history of Silver Lake Basin is well preserved due to the remoteness of the site. Most of the

relics of mining's past remain on-site, with three buildings still standing, and much of the mining

equipment still in place. All of the historic buildings around Silver Lake have either collapsed under

heavy snow loads or have been destroyed by avalanches. Some buildings were lost to various fires

during mining operations. Silver Lake Basin is an important part of the history of San Juan County.

The integrity of the site will remain intact due to the remote location.

Silver Lake, town site in forefront, power substation and assay office still standing. This was the location of the five

story boarding house and multiple other buildings.

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The mines in Silver Lake Basin are complex and interconnected with winzes, stopes, ore shoots, and

shafts. The complexity of the mine workings also makes the mine openings extremely dangerous

due to extensive vertical workings and the possibility of inadequate ventilation leading to oxygen

deficiency which can asphyxiate persons venturing too far underground.

Project Partnerships and Funding

The safeguarding of the Silver Lake Mines became a priority for CDRMS when ASARCo went

bankrupt and settled in court to provide clean-up funds for their legacy mining sites scattered

throughout the United States. The Silver Lake area received approximately 4.5 million dollars as

a set aside to clean-up and reclaim the ASARCo properties. CDRMS, CDPHE, and ARSG made

the Silver Lake mine safety closures a priority, so that the majority of funding could be preserved

for future environmental clean-ups to improve water quality in the Animas River. In 2010, the

project was funded by Colorado’s annual Office of Surface Mining, Reclamation, and

Enforcement (OSMRE) grant. OSMRE provided approximately half of the necessary funding,

and State Severance Tax funding filled in the remainder.

The Silver Lake Mine Site is an important part of Silverton's history and is a popular and well

known day trek. The San Juan County Historical Society and Mountain States Historical were

supportive of the project because of their interest in preserving the historic nature of the site.

Silver Lake is a treasure trove of historic mining machinery. Pictured here are parts of a steam pump, a column-

mount drill, and a pulley for a tram. Extreme care was taken to preserve the history of the site.

Silver Lake Reclamation Project

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Reclamation Plan

Utilizing Trimble GPS mapping and detailed land status analysis, property ownership and

individual mine safety closure specifications were developed. Due to the remote location and

high elevation, CDRMS opted to survey Silver Lake in one focused event utilizing seven

employees to locate the dangerous mine openings. Fifty-two mine safety closure locations were

identified and characterized using the CDRMS developed Mobile Brasscap application on the

Trimble GPS units. The data was then uploaded into the Brasscap database, which is Colorado's

mine safety closure database. Land Status was determined using ArcMap to georectify Land

Status Maps from the BLM, CDPHE, San Juan County, and ASARCo.

The mine safety closures were selected and designed to blend in with the historic nature of the

site. Closures of the mines were determined based on the attributes of current accessibility and

historic significance of the mines. The San Juan County Historical Society assisted with site

design by providing recommendations for grates and doors for certain locations. Grates with

doors were specified for many of the adits, so that visitors would be able to view the

underground mine workings from the safety of the surface, and private landowners could still

access their mine workings. Rock bulkheads made with locally scavenged rock from around the

site were specified for adits with less historical significance, or for mine openings that were

already collapsing and unstable. Vertical openings of significance were specified for grates with

doors, and special consideration was taken for excessive snow loading at these high elevations.

The reclamation plan included specifications for minimally impacting the site during

construction. Helicopters were required for all transportation of materials and equipment in

order to minimize land disturbance.

CDRMS crew at Silver Lake in 2010, developing the mine safety closure project

Silver Lake Reclamation Project

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Reclamation Construction Challenges

A number of unique and challenging issues were encountered, and eventually overcome, during

the life of the project. The Silver Lake mine safety closure project was an extremely remote

project located at a historically treasured location. The historic nature of the site was preserved

through meticulous attention to preserving the site. CDRMS specified appropriate closures for

historic sites while the contractor, K and P Property Design, LLC, was extremely careful to

maintain the historic look of the sites by avoiding historic objects or timbers, and working

around the object or incorporating the materials into the closures.

The very short construction season at this elevation was a challenge. The project was bid and

shown a year in advance, with the contractor allotted two summer seasons to complete the

project. K and P overcame the challenge of the short construction season by utilizing over

eleven workers and splitting into as many as four crews. One crew was responsible for materials

staging and helicopter delivery of materials. The other three crews were responsible for

installing mine closures.

The project presented significant challenges for delivery of materials and supplies to the high

elevation mine safety closure locations. CDRMS specified that helicopters would be required for

project execution. K and P opted to utilize a helicopter at least 3 days a week to transport

supplies around Silver Lake Basin. The use of the helicopter drastically reduced the time the

project took and lessened the impact to the sensitive alpine tundra environment.

The remote location of the project was also challenging for daily construction crew access. Due

to the long arduous steep hike up the headwall and into Silver Lake Basin from the trailhead

Helicopters were required by CDRMS, and K and P utilized helicopters three days a week to deliver materials to work locations

around Silver Lake Basin.

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lower down in Arrastra Gulch, K and P crews opted to camp at Silver Lake three nights each

week. K and P set up a minimalistic camp and endured the cold nights, rainy days, and profuse

lightning and thunder at an extreme elevation for the duration of the project.

Safety was another challenge due to the remote location and adverse weather. The crews were

constantly aware of the dangers of lightning and found shelter whenever necessary, often several

times each day! All crews were in contact via radios provided by the helicopter company, New

Air Helicopters. K and P had an additional staging area at a cabin directly below Silver Lake

Basin with additional crew members posted there in case of an emergency on the mountain.

Happily, there were no safety incidents or injuries during the project.

Reclamation Construction

The project Pre-Bid was held in September 2011 and the project was awarded to K and P Property

Design, LLC (K&P) for a low bid of $563,775.00. Two summer seasons were allotted in the project

schedule for construction, but K&P completed the work in less than three months during the summer

of 2012.

The Silver Lake Project was a meticulously organized and expertly constructed project. Due to the

remoteness of Silver Lake Basin, a helicopter from New Air Helicopters, LLC out of Durango,

Colorado was used on a near daily basis to deliver materials and transport people around Silver Lake

Basin. Construction materials and tools were staged at Gold Lake in Little Giant Basin and the

helicopter long-line dropped the materials at the mine openings. K&P camped on-site Monday

through Thursday during construction on the south side of Silver Lake. Thirty horizontal mine

openings (adits), 18 vertical openings (shafts and stopes), and one hazardous facility (water well)

were safeguarded using closure methods that included hand backfills, steel-grated shaft closures,

polyurethane foam closures, corrugated steel adit closures, grated adit closures, rock bulkhead

closures, and wire rope netting closures.

Mine safety closures were blended into the site, to maintain the historic integrity of Silver Lake Basin. Personnel from the

ASARCo Trust periodically observed some of the construction activities during the closure installations.

Silver Lake Reclamation Project

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Here are two vertical openings closed with grates and locking doors. The closures blend into the surroundings, while

providing safety to hikers and backcountry enthusiasts.

CDRMS and the contractor went above and beyond to blend the closures with the surroundings. On the left is a walkway and hand

railing installed over a grated stope. The trail historically went directly over the open stope, via a collapsing bridge of loose material.

The trail was maintained over this grated mine safety closure. On the right a worker installs the lock in a bulkhead closure.

Silver Lake Reclamation Project

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Reclamation Success

The overall site work involved difficult access, remote locations, high elevations, and extremely

dangerous mine openings in a historically sensitive, popular hiking area. CDRMS was able to

overcome the challenges and install mine safety closures that preserve the history of Silver Lake

Basin, saving ASARCo restoration trust funds for future hardrock environmental clean-ups. The

success of this project is therefore two-fold: Great success achieved in meeting the challenges of an

extreme remote location, steep topography, alpine storms, historic nature of the site, and the short

construction season; coupled with the successful partnerships formed with local and state entities to

preserve funding available for use on environmental clean-ups to improve water quality. By using

Colorado’s OSMRE funds to address the physical mining hazards in this remote area, more of the

trust fund is available to improve the aquatic health and water quality in the Animas River.

Silver Lake, a “hanging lake” or “tarn” at 12,186 feet

above MSL in the upper glacially-scoured cirque basin

above Arrastra Gulch and the Animas River